1. FIELD OF THE INVENTION
The present invention relates to golf cups for artificial golf greens, and more particularly, to a golf cup for use with a sand/granulate filled turf whereby the play action of a bent grass golf green cup is replicated in a golf cup for a simulated bent grass golf green surface for true golf play.
2. DESCRIPTION OF THE PRIOR ART
Natural grass golf greens are preferably made with bent grass which has a very distinct and desired playing character. The golf cups which are inserted into a bent grass green have their top edges recessed below the surface of the green in the golf hole whereby, as a golf ball is putted toward the hole with more force than is required for the ball to just drop in the hole, the ball bounces against the opposite side of the hole. It hits either the grass layer or the earth-grass root transition area below the grass layer, or the exposed earth below the transition area, to either drop in the cup or possibly bounce out due to its momentum, spin rate, and the vertical location it strikes the opposite side of the hole from its direction of entry.
In an effort to reduce the expense of golf green maintenance and to eliminate the problems which often occur in golf greens such as burning (dead grass), localized loss of the grass, irregular surfaces, pocking by golf balls and footprints, and even intentional destruction, golf course owners have come to accept artificial golf greens such as Tour-True.TM. produced by U.S. Indoor Golf of San Francisco, Ca., as a substitute for real grass. This product simulates a bent grass golf green and replicates the play of natural grass but yet is close to maintenance free. The Tour-True.TM. surface, in particular, consists of a durable polypropylene carpet fiber and a shock absorbent felt-like underpad. The carpet fiber is filled with a formulated, noncompactable, granular dressing which provides a surface that putts true like a real bent grass green. The speed of an artificial green such as Tour-True.TM. can be adjusted by varying the amount of top dressing. Such greens can be used indoors or outdoors and particularly for putting greens, target greens, putting courses, miniature golf, and even for landscape use. In outdoor applications, the artificial green maintains a consistent surface under all "playable" weather conditions.
One problem with these artificial greens has been due to the fact that the simulated surface is not the same as real earth or grass immediately below the playing surface. When the golf hole is cut in an artificial green, the sand particulate or granular dressing in the carpet fiber surrounding the hole tends to fall into the hole and the carpet fibers surrounding the hole then tend to bend over toward the hole causing an increasing depression in the green immediately surrounding the hole. In order to prevent this breakdown of the lip of the hole, it is necessary to seat the golf cup in the hole at a much higher position in the hole than in a real grass green in order to support the carpet fibers and top dressing surrounding the hole and prevent the deterioration of the lip of the hole. The cup is arranged to fit about 1/8 to 3/16 of an inch below the tips of the upstanding fibers adjacent the hole. As a result, the inside of the golf hole has a hard liner immediately below the playing surface. It is not comparable to the grass-earth transition area disposed above the cup rim in a real grass green whereby the play of a hole located in a real bent grass golf green has not been accurately replicated. It has not been until the development of the present invention through trial and error that the property of true play, the same as a natural bent grass golf hole, is replicated when a ball is putted into the improved golf cup of a simulated bent grass green.